Pedestrian crossing

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This crosswalk is used by students at Purchase College, NY.
Zebra crossing in Edinburgh, Scotland, UK

A pedestrian crossing or crosswalk is a place designated for pedestrians to cross a road. Crosswalks are designed to keep pedestrians together where they can be seen by motorists, and where they can cross most safely across the flow of vehicular traffic.

Marked pedestrian crossings are often found at intersections, but may also be at other points on busy roads that would otherwise be too unsafe to cross without assistance due to vehicle numbers, speed or road widths. They are also commonly installed where large numbers of pedestrians are attempting to cross (such as in shopping areas) or where vulnerable road users (such as school children) regularly cross. Rules govern usage of the pedestrian crossings to ensure safety; for example, in some areas, the pedestrian must be more than halfway across the crosswalk before the driver proceeds.

Signalised pedestrian crossings clearly separate when each type of traffic (pedestrians or road vehicles) can use the crossing. Unsignalized crossings generally assist pedestrians, and usually prioritise pedestrians, depending on the locality. What appear to be just pedestrian crossings can also be created largely as a traffic calming technique, especially when combined with other features like pedestrian priority, refuge islands, or raised surfaces.

History

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Pedestrian crossings were common in the Roman city of Pompeii.

Pedestrian crossings already existed more than 2000 years ago, as can be seen in the ruins of Pompeii. Blocks raised on the road allowed pedestrians to cross the street without having to step onto the road itself which doubled up as Pompeii's drainage and sewage disposal system. The spaces between the blocks allowed horse-drawn carts to pass along the road.

Police notice explaining the operation of the first pedestrian crossing signal.

The first pedestrian crossing signal was erected in Bridge Street, Westminster, London in December 1868. It was the idea of John Peak Knight, a railway engineer, who thought that it would provide a means to safely allow pedestrians to cross this busy thoroughfare. The signal consisted of a semaphore arm (Manufactured by Saxby and Farmer, who were railway signaling makers), which was raised and lowered manually by a police constable who would rotate a handle on the side of the pole. The semaphore arms were augmented by gas illuminated lights at the top (green and red) to increase visibility of the signal at night. However, in January 1869, the gas used to illuminate the lights at the top leaked and caused an explosion, injuring the police operator. No further work was done on signalled pedestrian crossings until fifty years later.[1]

In the early days of the 20th century car traffic increased dramatically. A reader of The Times wrote to the editor in 1911:

"Could you do something to help the pedestrian to recover the old margin of safety on our common streets and roads? It is heartrending to read of the fearful deaths taking place. If a pedestrian now has even one hesitation or failure the chance of escape from a dreadful death is now much less than when all vehilcles were much slower. There is, too, in the motor traffic an evident desire not to slow down before the last moment. It is surely a scandal that on the common ways there should be undue apprehension in the minds of the weakest users of them. While the streets and roads are for all, of necessity the pedestrians, and the feeblest of these, should receive the supreme consideration."[2]

Types

Crossings are of various types.

  • Unmarked crossings may occur at any intersection. In the US these are called "unmarked crosswalks."[3]
  • The simplest marked crossings may just consist of some markings on the road surface. In the US these are known as "marked crosswalks." In the UK these are often called Zebra crossings, referring to the alternate white and black stripes painted on the road surface. Depending on local laws, pedestrians crossing the road may or may not have priority over road traffic when using the crossing. If the pedestrian has priority, then they have an incentive to use the crossing instead of crossing the road at other places. In some countries, pedestrians may not have priority, but may be committing an offence if they cross the road elsewhere (see Jaywalking).
  • Some crossings have special signals consisting of electric lamps or light-emitting diode (LED) panels. The signals allow pedestrians and road traffic to use the crossing alternately. On some traffic signals, pressing a button is required to trigger the signal. These signals may be integrated into a regular traffic light arrangement or may be on their own if the crossing is not at an intersection. In some countries approach radar or electro-magnetic detectors buried in the road surface are used to measure the speed of oncoming vehicles and used to set the lights to red if a speeding offence is detected. This has the effect of enforcing the local speed limit without the necessity of issuing speeding citations, etc. Audible or tactile signals may also be included to assist people who have poor sight. In many cities, some or most signals are equipped with countdown timers to give notice to both drivers and pedestrians the time remaining on the crossing signal.
  • Sites with extremely high traffic, or roads where pedestrians are not allowed (freeways or motorways) may instead be crossed via pedestrian bridges or tunnels. A variation on the bridge concept, often called a skyway or skywalk, is sometimes implemented in regions that experience inclement weather.

Special markings are often made on the road surface, both to direct pedestrians and to prevent motorists from stopping vehicles in the way of foot traffic. There are many varieties of signal and marking layouts around the world and even within single countries. In the United States, there are many inconsistencies, although the variations are usually minor. There are several distinct types in the United Kingdom, each with their own name.

Pedestrian refuges or small islands in the middle of a street may be added when a street is very wide, as these crossings can be too long for some individuals to cross in one cycle. In places where there is very high pedestrian traffic, exclusive traffic signal phases for pedestrians (also known as Barnes Dances) may be used, which stop vehicular traffic in all directions at the same time. Another relatively widespread variation is the curb/kerb extension (also known as a bulb-out) which narrows the width of the street and is used in combination with crosswalk markings.

Distinctions by region

North America

In the United States, crosswalks are sometimes marked with white stripes, though many municipalities have slightly different methods, styles, or patterns for doing so, and the styles may vary over time as intersections are built and reconstructed. There are two main methods for road markings in the United States. Most frequently, they are marked with two thick white lines running from one side of the road to the other. A third "stop line", which is very thick and extends only across lanes going into the intersection, is usually also present. Left-turn stop lines are often set further back, to avoid conflict with left-turning traffic coming from the roadway on the right. The stop line acts as the legally mandated stopping point for vehicles, and discourages drivers from stopping in the middle of the crosswalk. The other method involves the use of the more easily visible continental stripes (like UK zebra crossings), which are becoming more popular in place of the two-line variant[citation needed]. The designs used vary widely between jurisdictions, and often vary even between a city and its county (or local equivalents). Where a road forms part of a city limit or other such political boundary—thus making the intersection shared between the two—there may be more than one design used on different sides, depending upon which government painted it.

Crosswalk pavement marking variants per the U.S. FHWA.

Marked crosswalks are usually placed at traffic intersections or crossroads, but are occasionally used at mid-block locations where pedestrian generators are present such as at transit stops, schools, retail, or housing destinations. In the United States, these so-called "mid-block" crossings may include additional regulatory signage such as "PED XING" (for "pedestrian crossing"), flashing yellow beacons, stop or yield signs, or by actuated or automatic signals. Some more innovative crossing treatments include in-pavement flashers, yellow flashing warning lights installed in the roadway, or HAWK beacon, an overhead signal with two pair of red beacons above an amber beacon, when a pedestrian is detected or actuates the device it begins a sequence of amber flashing followed by a solid red [when vehicles may not cross], followed by a flashing red phase that allows motorists to proceed, only if the pedestrian[s] are clear of the travel way. In the United States, crossing laws vary from state to state and sometimes at the local level. All states require vehicles to yield to a pedestrian who has entered a marked crosswalk.[3] To gain the right-of-way in some parts of Canada, however, the pedestrian holds out his hand in a position much like that used to shake hands, and steps off the curb.

A sign warning motorists to yield to those crossing the crosswalk.

At crossings controlled by signals, the most common variety is arranged like this: At each end of a crosswalk, the poles which hold the traffic lights also have white "walk" and Portland Orange "don't walk" signs. These particular colors are used in North America (excluding Quebec[4]) to provide conspicuity against the backdrop of red, yellow, and green traffic lights. Modern signals generally use pictograms of an orange upraised hand and a white walking pedestrian rather than words. As a warning, the "don't walk" or hand signals begin to blink when the transition to "don't walk" is imminent. This normally occurs several seconds before the light turns yellow, usually going solid orange when the traffic light turns yellow. Some signals continue flashing the hand/"don't walk" phase during the yellow light, and go steady at red. Sometimes the "walk" signal does not come on in a steady pattern; it will sometimes blink/flash on and off instead to warn pedestrians to cross the street with caution due to the possibility of a turning vehicle. On pedestrian signals displaying text, "don't walk" is spelled without an apostrophe so that it fits easily on the sign. A black baffle is customarily placed in front of the lights to shield them from the sun and increase their visibility, as well as protect them from damage.

Legally speaking, in most states crosswalks exist at all intersections meeting at approximately right angles, whether they are marked or not.[5] All states except Maine and Michigan require vehicles to yield to a pedestrian who has entered an unmarked crosswalk.[3] In some cities in the US, other methods of pedestrian detection are being tested, including infrared and microwave technology, as well as weight sensors built in at curbside. On fully actuated signals, or semi-actuated traffic signals, pressing the button to cross a smaller side street will cause an "instant walk signal". In most states, drivers only have to wait until the pedestrian has finished crossing the half of the crosswalk that the driver is driving on, after which the driver may proceed; however, in some states, such as Utah, if the driver is in a school zone with the lights flashing, the driver must wait until the entire crosswalk is clear before he may proceed.

Three-state signal sequence with textual messages typical for the USA; words may be replaced by symbols.

Crosswalks have also been adapted for the blind by adding accessible pedestrian signals [APS] that include speakers at the pushbutton for each crossing location. The current standards in the US (Manual on Uniform Traffic Control Devices, 2009, Sections 4E.09 - 4E.13) require APS units to have a pushbutton locator tone, audible and vibrotactile walk indications, a tactile arrow aligned with the direction of travel on the crosswalk, and to respond to ambient sound. The pushbutton locator tone is a beep or tick, repeating at once per second, to allow people who are blind to find the device. The walk indication may be a rapid ticking tone or a speech message, accompanied by a vibrating arrow on the APS during the walk signal. APS are supposed to be set to be heard only 6 to 12 feet from the device to be easy to detect from a close distance but not so loud as to be intrusive to neighboring properties [originally many versions of audible pedestrian signals used extremely loud buzzers or even bird-like whistles to convey information, but new standards have improved upon some of these earlier devices]. [6]

United Kingdom

In the United Kingdom (and in many current or former Commonwealth countries as well), it is illegal for drivers to park upon the 'zig zag' lines either side of a pedestrian crossing. This is to ensure pedestrians' view of oncoming traffic is not obscured.
A puffin crossing in the UK

In the United Kingdom and certain parts of the Commonwealth of Nations, animal names are often used to distinguish several types of such crossings:

Belisha beacons are found at zebra crossings. The other types of crossing use coloured pictogram lights, depending on the intended users of the crossing this will be a man, a bicycle or a horse.

Australia

In Australia, the terminology pedestrian crossing is used.

Pictograms are standard on all traffic light controlled crossings. Like some other countries, a flashing red sequence is used prior to steady red to clear pedestrians. Moments after, in some instances, a flashing yellow sequence (for motorists) can begin indicating that the vehicles may proceed through the crossing if safe to do so; this is fairly uncommon however. In districts with heavier traffic warranting the use of a traffic light such as inner city areas, the equivalent of the US 'standard' configuration is used.

Only one usage derived from animal terminology is present in Australia, the Zebra Crossing. Zebra crossings are common in low traffic areas and their approaches may be marked by zig zag lines.

Reflector signposting is used at crossings in school zones, however given that most school crossings in the country are manned, these signs only serve as a warning to motorists.

Signals

Call buttons

The button one pushes to activate the crosswalk signal

Reports suggest that many walk buttons in some areas, such as New York City and the United Kingdom, may actually be placebo buttons designed to give pedestrians an illusion of control while the crossing signal continues its operation as programmed.[7][8] In New York City, many such buttons are now rendered useless due to the automatic programming of the crosswalk, and other buttons may work, but only at certain times of day or certain periods of the year.[7] In the United Kingdom, pressing a button at a standalone pedestrian crossing that is unconnected to a junction will turn a traffic light red immediately, but this is not necessarily the case at a junction.[8] In Boston, Massachusetts, some busy intersections are programmed to give a pedestrian cycle during certain times of day (so pushing the button is not necessary) but at off-peak times a button push is required to get a pedestrian cycle. In neighboring Cambridge, Massachusetts, a button press is always required if a button is available, though the city prefers to build signals where no button is present and the pedestrian cycle always happens between short car cycles. In both cases the light will not turn immediately, but will wait until the next available pedestrian slot in a pre-determined rotation.[9]

Countdown timers

A pedestrian signal in California with countdown timer

Lua error in package.lua at line 80: module 'strict' not found. Some pedestrian signals integrate a countdown timer, showing how many seconds are remaining for the clearing phase. The 2009 edition of the US Manual on Uniform Traffic Control Devices (MUTCD) requires countdown signals be used at all signalized intersections with pedestrian clearance intervals (flashing upraised hand phases) longer than 7 seconds.

In Mexico City, as in São Paulo, Brazil, the walking man moves his feet.

In Taiwan there is generally no crossing manner. The majority of crossings cannot be controlled by pedestrians, although there are exceptions in Taipei. All the crossings feature animated men who will walk faster immediately before the traffic signal will change. There is also always a countdown timer.

Variations

A pedestrian crossing with a Vienna Convention standard sign indicating to motorists that they must give priority to pedestrians using it.

In some countries, instead of "don't walk", a depiction of a red man or hand indicating when not to cross, the drawing of the person crossing appears with an "X" drawn over it.

Some countries around the Baltic Sea in Scandinavia duplicate the red light. Instead of one red light, there are two which both illuminate at the same time.

In many parts of eastern Germany, the design of the crossing man (Ampelmännchen) has a hat.

Temporary signals

Portable pedestrian crossing signal at a road work site

In certain circumstances, there are needs to install temporary pedestrian crossing signals. The reasons may include redirecting traffics due to roadworks, closing of the permanent crossing signals due to repairs or upgrades, and establishing new pedestrian crossings for the duration of large public events.

The temporary pedestrian crossings can be integrated into portable traffic signals that may be used during the roadworks, or it can be stand-alone just to stop vehicles to allow pedestrians to safely cross the road without directing vehicle movements. When using the temporary pedestrian crossings signals for roadworks, there should be consideration on signal cycle time. The pedestrian crossing cycles may add longer delay to the traffics which may require additional planning on road work traffic flows.

Depending on the duration and the nature of the temporary signals, the equipment can be installed in different way. One way is to use the permanent traffic signals mounted temporary poles such as poles in concrete-filled barrels. Another way is to use portable pedestrian crossing signals.[10]

Enhancements for disabled people

Tactile paving next to a crosswalk

Pedestrian controlled crossings are sometimes provided with enhanced features to assist the disabled (disabled people). Enhancements may include:

  • Tactile cones near or under the control button. These rotate or shake when the pedestrian signal is green - the image of a "green man". This is for pedestrians with visual impairments.
  • Tactile surfacing pattern (or tactile paving) laid flush within the adjacent footways (US: sidewalks), so that visually impaired pedestrians can locate the control box and cone device and know when they have reached the other side. In Britain, different colours of tactile paving indicate different types of crossings; yellow (referred to as buff coloured) is used at non-controlled (no signals) crossings, and red is used at controlled (signalised) locations.
  • Audible signals, such as beeps or a rapid tick in order to help blind or partially sighted pedestrians; or a short recorded message, as in Scotland, Hong Kong, Singapore and some parts of Canada (moderate to large urban centres), the United States, including Michigan, Massachusetts, Maryland and Texas. San Francisco, California has one of the most comprehensive Accessible Pedestrian Signal policies in the United States, and has installed more than 1,000 audible devices.[11] In Japan, various electronic melodies are played, often of traditional melancholic folk songs such as "Tōryanse" or "Sakura". In Croatia, Denmark and Sweden, beeps (or clicks) with long intervals in-between signifying "don't walk" mode and beeps with very short intervals signifying "walk" mode.
  • A vibrating button in addition to an audible signal is used in Australia, Germany, and some parts of the United States, Greece, Ireland, and Hong Kong to assist hearing-impaired people (see also 'cones' at the top of this list)
  • Electrostatic, touch-sensitive buttons; these require no force to activate. To confirm that a request has been registered, the buttons usually emit a chirp or other sound. They also offer anti-vandalism benefits due to not including moving parts which are sometimes jammed on traditional push-button units.
  • In Perth, Western Australia, an extended phase system called 'Keywalk' was developed by the Main Roads Department of Western Australia in response to concerns from disability advocates about the widening of the Albany Highway in that city in the mid-1990s. The Department felt that extending the walk phase permanently on cross streets would cause too much disruption to traffic flow on the highway and so the ‘Keywalk’ system was developed to allow for those who needed an extended green light phase to cross the road safely. A small electronic key adjusted the green/walk and flashing red/complete crossing phases to allow more time for the key holder to complete the crossing of the highway safely. The system was first installed at the junction of Albany Highway and Cecil Avenue.[12] It is unclear what became of this system.

Lighting

Crosswalk with overhead lighting, and internally illuminated overhead crosswalk signs

There are two types of crosswalk lights: those that illuminate the whole crosswalk area, and warning lights.[13]

The Illuminating Engineering Society of North America currently provides engineering design standards for highway lighting. In the USA in conventional intersections, area lighting is typically provided by pole-mounted luminaires.[14] These systems illuminate the crosswalk as well as surrounding areas, and do not always provide enough contrast between the pedestrian and his or her background.

There have been many efforts to create lighting scenarios that offer better nighttime illumination in crosswalks. Some innovative concepts include:

Illuminating lights

  • Bollard posts containing linear light sources inside. These posts have been shown to sufficiently illuminate the pedestrian but not the background, consequently increasing contrast and improving pedestrian visibility and detection.[15] Although this method shows promise in being incorporated into crosswalk lighting standards, more studies need to be done.[16][17]
  • Festooned strings of light over the top of the crosswalk.[18]

Warning lights

  • In-pavement lighting oriented to face oncoming traffic.[19]
  • In-pavement, flashing warning lights oriented upwards.[20]
  • Pole-mounted, flashing warning lights (mounted similar to a traffic signal).
  • Pedestrian warning signs enhanced with LED lights either within the sign face[21] or underneath it.[22][23]

In areas with heavy snowfall, using in-pavement lighting can be problematic, since snow can obscure the lights, and snowplows can damage them.

Railway pedestrian crossings

Finland

A railway pedestrian crossing in Jyväskylä, Finland.

Fences in the footpath approaching the crossing force pedestrians and bicycles to slow down to navigate a zigzag path, which also tends to force that user to lookout for the train.

New South Wales

Pedestrian crossings across railways may be arranged differently, such as in New South Wales. Here they consist of

  • a barrier which closes when a train approaches;
  • a "Red Man" light ; no light when no train approaching
  • an alarm

France

In France, when a train is approaching, a red man is shown with the word STOP flashing in red (R25 signal).[24]

United Kingdom

Most often when a footpath crosses a railway in the United Kingdom, there will be gates or stiles protecting the crossing from wildlife and livestock. In situations where there is little visibility along the railway, or the footpath is especially busy, there will also be a small set of lights with an explanatory sign. When a train approaches, the signal light will change to red and an alarm will sound until the train has cleared the crossing.

Pedestrian cross striping

Striping machine

Road marking machine working in Bahrain, December 2012.[25]

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Pedestrian cross striping machine is special equipment professionally used for paint zebra lines on the intersections or other busy road sections. Because of the characteristics of zebra cross, parallel stripes not long, the striping machine is often small hand-guide road marking machine, convenient to turn direction. The widths of stripe are 350mm, 400mm, 450mm, 500mm and 600mm. There is discrepancy between the engineer regulations in different countries. The marking shoe of pedestrian cross striping machine, which determines marking lines’ width, is much wider than other pavement marking machines. Some simple marking shoe with wheels is also applied to deal the road striping.

Painting construction

The section of road should be swept clean and kept dry. Pull a guiding line straight and fix the two ends on the ground. Then spray or brush a primer layer on the asphalt or concrete surface. The powder state thermoplastic paint needs melt into molten state for painting. Pull or push the striping machine with the guide rod along the guiding line to keep the zebra stripes straight and beautiful. Generally, the hand-push road striper is backward coating and the self-propelled type is forward coating to conform the body force exert habit.

Safety

The safety of unsignalled pedestrian or zebra crossings is somewhat contested in traffic engineering circles.

Research undertaken in New Zealand showed that a zebra crossing without other safety features on average increases pedestrian crashes by 28% compared to a location without crossings. However, if combined with (placed on top of) a speed table, zebra crossings were found to reduce pedestrian crashes by 80%.[26]

A five-year U.S. study of 1000 marked crosswalks and 1000 unmarked comparison sites found that on most roads, the difference in safety performance of marked and unmarked crossings is not statistically significant, unless additional safety features are used. On multilane roads carrying over 12,000 vehicles per day, a marked crosswalk is likely to have worse safety performance than an otherwise similar unmarked location, unless safety features such as raised median refuges or pedestrian beacons are also installed. On multilane roads carrying over 15,000 vehicles per day, a marked crosswalk is likely to have worse safety performance than an unmarked location, even if raised median refuges are provided. The marking pattern had no significant effect on safety. This study only included locations where vehicle traffic was not controlled by a signal or stop sign.[27]

See also

References

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  2. The Times, Feb. 14, 1911, pg. 14: The Pedestrian's Chances.
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  5. See here (discussing the Uniform Vehicle Code and stating that "a crosswalk at an intersection is defined as the extension of the sidewalk or the shoulder across the intersection, regardless of whether it is marked or not."); see also California Vehicle Code section 275(a) ("'Crosswalk' is . . . [t]hat portion of a roadway included within the [extension] of the boundary lines of sidewalks at intersections where the intersecting roadways meet at approximately right angles, except the [extension] of such lines from an alley across a street")
  6. More information is available at www.apsguide.org
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  11. http://www.sfmta.com/services/streets-sidewalks/installation-requests/accessible-pedestrian-signals; http://lflegal.com/2010/03/sf-aps/
  12. Keywalk for the disabled is an Australian first (March 1995). Western Roads: official journal of Main Roads, Western Australia, 18(4), p.10. Perth: Main Roads Department.
  13. Illuminating Engineering Society of North America. American National Standard Practice for Roadway Lighting. Publication IESNA-RP-8-00. Illuminating Engineering Society of North America, New York, 2000.
  14. Hasson, P., P. Lutkevich, B. Ananthanarayanan, P. Watson, and R. Knoblauch. Field Test for Lighting to Improve Safety at Pedestrian Crosswalks. Presented at the 16th Biennial Transportation Research Board Visibility Symposium, Iowa City, Ia., 2002.
  15. Lua error in package.lua at line 80: module 'strict' not found.
  16. Press Releases | LRC Newsroom
  17. Bullough, J.D., X. Zhang, N.P. Skinner, and M.S. Rea. Design and Evaluation of Effective Crosswalk Lighting. Publication FHWA-NJ-2009-03. New Jersey Department of Transportation, Trenton, NJ, 2009.
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  21. Embedded LEDs in Signs, Federal highway Administration, May 2009
  22. Van Houten, Ron and & Malenfant, J.E. Louis, Efficacy of Rectangular-shaped Rapid Flash LED Beacons, Retrieved March 25, 2011
  23. Impacts of LED Brightness, Flash Pattern, and Location for Illuminated Pedestrian Traffic Control Device, Federal Highway Administration, May 2015
  24. Sécurisation des traversées piétonnes des voies de tramway, CETE Sud-Ouest
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